Research Publications (Food Safety)

Abstract BACKGROUND Alfalfa (Medicago sativa L.) has been used widely in preparing silage. However, forage legumes are prone to contamination by spoilage bacteria during fermentation. Nisin has broad‐spectrum antibacterial properties and has been applied as an inhibitor of rumen methane emissions. However, little research has been carried out on the application of nisin in silage.

Raw oyster meats may be contaminated with Vibrio parahaemolyticus and V. vulnificus. These Vibrio species have been strongly associated with severe and life-threatening conditions in immunocompromised individuals. Post-harvest treatment, such as freezing, affects Vibrio species present in oyster meats and the quality of oysters.

Background The Thermo Scientific™ SureTect™ Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus PCR Assay method is a real-time PCR method for the multiplex detection of Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus in seafood. Objective The Thermo Scientific SureTect Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus Assay was evaluated for AOAC Performance Tested MethodsSM certification.

The potential of using commercial peroxyacetic acid (PAA) for Vibrio parahaemolyticus sanitization was evaluated. Commercial PAA of 0.005 % (v/v, PAA: 2.24 mg/L, hydrogen peroxide: 11.79 mg/L) resulted in a planktonic cell reduction of >7.00 log10 CFU/mL when initial V. parahaemolyticus cells averaged 7.64 log10 CFU/mL.

The aim of the present study was to evaluate Vibrio parahaemolyticus occurrences in bivalve molluscs harvested from Sardinian coastal environments between 2013–2015.The prevalence of pathogenic V. parahaemolyticus isolates is based on the detection of the two major virulence genes thermostable direct haemolysin (tdh) and thermolabile hemolysin (trh) To assess changes between 2011–2018 in the prevalence of V.

The intestine is a host-pathogen interaction site and improved intestinal barrier function help to prevent disease in shrimp. Alginate oligosaccharides (AOS) are derived from resourceful brown algae. The intestine protection properties of AOS were widely recognized, and their benefits in fish have been reported. Nevertheless, there are no reports on AOS in shrimp and other crustaceans.

Gram-negative Vibrio species are major foodborne pathogens often associated with seafood intake that causes gastroenteritis. On food surfaces, biofilm formation by Vibrio species enhances the resistance of bacteria to disinfectants and antimicrobial agents. Hence, an efficient antibacterial and antibiofilm approach is urgently required. This study examined the antibacterial and antivirulence effects of chromones and their 26 derivatives against V. parahaemolyticus and V. harveyi.

Abstract A supplemental effect of Achyranthes aspera extract (200 mg/kg phytosterol) in diets was evaluated for Pacific white shrimp (Penaeus vannamei) on growth performance, digestibility, innate immunity, antioxidant capacity, and disease resistance against Vibrio parahaemolyticus. A fish meal and soybean meal‐based control diet (Con; protein 38.0% and lipid 8.7%) was formulated and five other diets were prepared by adding A.

Abstract Establishing efficient methods to combat bacterial biofilms is a major concern. Natural compounds, such as essential oils derived from plants, are among the favored and recommended strategies for combatting bacteria and their biofilm. Therefore, we evaluated the antibiofilm properties of peppermint oil as well as the activities by which it kills bacteria generally and particularly their biofilms.

Abstract Antibiotic drugs (ABD) are often used in shrimp farms to treat the disease when a bacterial diagnosis is presumed. This scenario was the impetus to carry out a field survey to define how ABD are employed in the State of Sonora, the second largest producer of shrimp in Mexico. Twenty‐nine farms were surveyed through their general managers.

Abstract An acute infectious disease of northern sheatfish (Silurus soldatovi) was found in a commercial aquaculture pond in Tianjin, China. Herein, two dominant bacterial strains were isolated from naturally diseased northern sheatfish and identified as Aeromonas veronii and Vibrio cholerae. Seven healthy and seven naturally diseased fish that were collected from the pond were used for the gut microbiota analysis by high‐throughput 16S rRNA gene sequencing.

Abstract The study aimed to evaluate the effect of tributyrin on the growth performance, survival, hypoxia tolerance, and nutrient digestibility of Pacific white shrimp fed 25% and 50% soybean meal (SBM) diets. Six experimental diets were formulated: (1) 25% SBM without tributyrin; (2) 25% SBM with 0.05% tributyrin; (3) 25% SBM with 0.1% tributyrin; (4) 50% SBM without tributyrin; (5) 50% SBM with 0.05% tributyrin; and (6) 50% SBM with 0.1% tributyrin.

Abstract Vibrio parahaemolyticus is a significant causal agent of acute hepatopancreatic necrosis disease (AHPND), with huge production losses of white leg shrimp, Litopenaeus vannamei, cultivated globally, including aquaculture farms in the Mekong Delta of Vietnam. Controlling this disease is critical because of the worldwide expansion of antimicrobial‐resistant V. parahaemolyticus isolates. The purpose of this study was to determine the frequency of multi‐antibiotic resistance (MAR) in V.

Abstract Soybean meal (SBM) is widely used in shrimp feed agro‐industry as a fish meal (FM) replacement. However, high levels of SBM may compromise animal health as a result of nutrient imbalance.

Abstract Phages depend on their bacterial hosts to replicate. The habitat, density and genetic diversity of host populations are therefore key factors in phage ecology, but our ability to explore their biology depends on the isolation of a diverse and representative collection of phages from different sources. Here, we compared two populations of marine bacterial hosts and their phages collected during a time series sampling program in an oyster farm.

The quorum sensing (QS) and c‐di‐GMP signaling pathways are intricately intertwined to control swarming in Vibrio parahaemolyticus strain RIMD 2210633. The QS signals which inhibit LuxOvp phosphorylation are essential for V. parahaemolyticus to swarm efficiently on surfaces. And LuxOvp regulates swarming in a mechanism that involves modulating c‐di‐GMP levels, which may be intracellularly compartmentalized in V. parahaemolyticus.

Abstract Hybrid grouper (E. lanceolatu × E. fuscoguttatus) is a high economic value cultured species in Southeast Asia. There is a dangerous stage during its body length from 7 cm to 15 cm, and rotten fins and enteritis often occur in this period.

Abstract A 100‐day feeding trial was conducted to investigate the influences of dietary lipid levels on the immunity and mechanism in abalone Haliotis discus hannai Ino. Abalones (initial weight: 10.98 ± 0.05 g) were fed with graded levels of dietary lipid, which were 15.73, 23.41, 31.72, 38.25, 46.35, 55.63, 61.70 and 67.19 g/kg.

Abstract An 8‐week trial was performed to evaluate tributyrin effects on growth, disease resistance, lipid metabolizing, distal intestinal inflammation‐, tight junctions‐ and apoptosis‐related gene expressions caused by high‐level cottonseed protein concentrate (CPC) substitution of fishmeal. Fish were fed one fishmeal (50% fishmeal) and six CPC diets (27.5% fishmeal and 25.2% CPC).

Abstract The present study was conducted to investigate the effects of yeast culture on the growth, hepatic antioxidant capacity, intestinal barrier and microflora of fish fed a high‐cottonseed protein diet.

Abstract A 60‐day feeding trial was carried out to investigate the effects of fish protein hydrolysate (FPH) in high lupin meal (LM) diets on growth, health and immunity of barramundi. Fish were fed a fishmeal‐based control diet (FM) and three test diets to replace 75% fishmeal protein in the control diet by lupin meal alone (LM), lupin meal with FPH (LM+FPH) and fermented lupin meal with FPH supplementation (FLM+FPH).

Although the microbial ecology of integrated rice-crayfish farming systems is receiving increasing attention with the expanding application area in China, the effects of rice transplanting patterns on the microbial community of water, sediment and Procambarus clarkii intestine in rice-crayfish system has yet to be determined.

Vibrio vulnificus is a multi-host pathogenic species currently subdivided into five phylogenetic lineages (L) plus one pathovar with the ability to infect fish due to a transmissible virulence plasmid. This plasmid (or a fragment of it) has been transmitted between lineages within the species, contributing to the evolution of V. vulnificus. This study aimed to provide an experimental approximation to the V.

Plant-derived alternatives to antibiotics are of great concern. The goal of this work was to enhance the Hu Zhang (Polygonum cuspidatum) extraction procedure against non-O1/O139 V. cholerae (HZE), identify the antibacterial components, analyze the mechanism of action, and investigate its potential in prawn storage.

Plankton-bacteria interactions may play essential roles in maintaining the persistence of pathogenic Vibrio spp. However, the actual plankton host of the toxigenic Vibrio parahaemolyticus that harbors thermostable direct hemolysin (TDH) and TDH-related hemolysin (TRH) remains unclear.